Escaped farmed salmon could cause problems, council warnsDFO says unlikely the fish had any disease or illness

Posted: May 16, 2013 3:28 PM NT

The Salmonid Council of Newfoundland and Labrador warns a recent escape of farmed salmon could cause problems with the wild Atlantic salmon population.

Department of Fisheries and Oceans Canada officials confirmed this week that farmed salmon escaped from an aquaculture site in the Fortune Bay area, and have turned up in the Garnish River.

Council president Don Hutchens said it poses multiple threats to the wild salmon, such as potential interbreeding between wild and farmed salmon, and spreading of the infectious salmon anemia (ISA) virus.

He said the DFO is playing down the issue.

"We told them it was going to happen, they told us that we shouldn't fear about it, but there is no signs to say that we shouldn't fear," Hutchens said.

"In fact, what we do know is everywhere there's been a finfish farm agricultural site, wild Atlantic salmon populations have drastically declined," he added.

Hutchens said part of the problem is that the DFO does not report on escapes that it calls trickle escapes.

"We think that trickle escapes are quite significant — almost to the point that they're almost major escapes when they're done collectively. You could have up to a hundred salmon a day trickling out through the nets and escaping over the sides," Hutchens said.

"You add those up for the year, and you have quite a significant number of farmed salmon escaping into the wild."

No cause for concern, DFO says

Geoff Perry, with the regional aquaculture management of DFO, said there are no indicators to cause concern about spreading infection or disease to the wild population of the fish.

"The animals we sampled last week, we're running them through a full sweep of pathogen screening so we'll have some information on that in the next couple weeks," Perry said.

"But from what we visually looked at, these fish, there's no sea lice on them, and they're not exhibiting any signs of disease or external signs of disease," he added.

He said the fish likely got out during an increase in water levels during the fall or winter season.

"What's probably happened here is these fish got out some time over the winter during a storm, and eventually just poked their nose into a place where the environmental conditions were a little more favourable than the open ocean," Perry said.

However, Perry said there is concern that interbreeding will lead to a weaker generation of salmon in the wild.

"There's concern that if wild and farmed fish interbreed — that the resulting hybrids, farm-wild fish hybrids — will be less fit for the wild environment because farm salmon had been domesticated for traits that make them a very good food fish, but those same traits don't make for good survival in the wild, whereas wild fish have traits that make them very good to survive in the wild," Perry said.

Perry said they did not receive a report from any of the farms in the area, so they do not know which farm the fish escaped from.

Rare occurrence, association says

Cyr Couturier, the executive director of the Newfoundland Aquaculture Industry Association, repeats sentiments that the likelihood of ISA spreading is low.

"These are naturally occurring diseases that come from wild fish that are passed on to salmon in cages," Couturier said. "There's regular inspection and testing for that almost on a continuous basis by the government agencies and [Canadian Food Inspection Agency]."

Couturier also said that concern about interbreeding between wild and farmed salmon is low.

"This is one escape. It's not a huge escape, from what we can tell yet, and we don't think that there's going to be much interbreeding," he said. "We haven't seen it in 30 years in Newfoundland and Labrador."

Couturier said the association is doing an investigation to find out where exactly the fish escaped from.